A vehicle may include an alternator for converting mechanical energy into electrical energy. The electrical energy produced by the alternator may be stored in an electrical energy storage device for future consumption or the electrical energy may be consumed by electrically powered devices as the electrical energy is produced. Recently, electrical loads within the vehicle have increased and are expected to increase further as autonomous vehicles are put into production. For example, some vehicles include electrically assisted steering and electrically driven climate control systems. Autonomous vehicles may include object and distance observing sensors as well as enhanced communications systems and actuators to position, stop, and accelerate the vehicle. The electrical loads may increase well beyond that which a medium duty alternator may provide. Further, a speed of an engine driving the alternator may vary such that the engine drives the alternator at speeds where the alternator operates less efficient than may be desired. Consequently, the alternator electrical output may be at times insufficient to supply the electrical load unless the alternator is sized large. However, increasing the alternator size may increase vehicle mass, thereby decreasing vehicle fuel efficiency. As such, it would be desirable to provide an alternator that has high output capacity with a reduced mass.
The inventor herein has recognized the above-mentioned disadvantages of a conventional alternator and has developed an electrical machine, comprising: a housing; a first field winding within the housing; a first armature winding; a second field winding, the first field winding and the first armature winding at least partially wrapped by the second field winding; and a second armature winding, the first field winding and the first armature winding at least partially wrapped by the second armature winding.
By providing a first field winding and a first armature winding at least partially wrapped by a second field winding, it may be possible to provide the technical result of providing an alternator with increased electrical output in a smaller package. Additionally, the field and armature windings may provide for maintaining a load on an engine while a speed of an ancillary device coupled to the electric speed may be adjusted. In particular, the speed of the ancillary device may be adjusted into an operating range where efficiency of the ancillary device may be improved.
The present description may provide several advantages. In particular, the electric machine may increase electrical output. Further, a load provided to an engine providing motive force to the electric machine may be maintained while output of the electric machine is adjusted to operate an ancillary mechanically driven device in an efficient operating speed range. Further still, the electric machine may be configured in different packaging schemes to reduce physical dimensions of a vehicle powertrain.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.